Most prior art feed troughs for use in an open field utilize some type of legs or support members as a means for maintaining the trough in an upright position so that it is accessible to the animals. For example, U.S. Pat. Nos. 654,427, 927,197, 1,378,263, 1,727,610, 1,742,019, 1,749,808 and 2,691,362. The disadvantage with such legs or support members is that they are rigid and can break or give out if the animal steps in the feed trough. In addition, the legs and support members make it difficult to transport and relocate these feed troughs to remote locations, as is often necessary when feeding livestock on an open rangelands.
Also known in the art are various semicircular feed troughs that are placed directly on the ground without legs or support members. For example, U.S. Pat. No. 700,522. While a semicircular feed trough does not have legs or support members that may break, there is nothing to prevent the trough from tipping or turning over when an animal steps in the trough, thereby spilling the feed and making the trough inaccessible to the livestock.
Although the present designs for feed troughs are adequate for some uses, it would be advantageous to have a simple and inexpensive design for a feed trough that could not be damaged by livestock and would remain accessible to the animals even when stepped in, yet could be easily transported and maintained.